Narcissus and Daffodil

294 N.P.D. Nanayakkara and J.K. Bastos
UV spectra of galanthamine, lycorine and nivalidine. All three compounds had
similar UV spectra with maxima at 222 and 286 nm. A quantitative spectrophotometric
method was developed for the determination of galanthamine at 286 nm.
The relationship between the fluorescence characteristics and chemical structure
of galanthamine, lycorenine, lycorine, tazettine and vittatine was studied by
Bruno and De Laurentis (1982). All these compounds had emission maxima at
about 320 nm and excitation maxima at 290 nm. A linearity between the fluorescence
intensity and concentration over 1–6 µM/l was observed, and the detection
limit was 0.05 µg/ml.
Burgudjiev and Grinberg (1993) analysed the UV and fluorescence spectra of
galanthamine base and its hydrobromide in water, ethanol and n-hexane, and
limits of detection for UV spectrophotometry and fluorometry were established.
Yamboliev and Mikhailova (1985) described a spectrofluorometric method for
the determination of galanthamine in biological fluids. Galanthamine was
extracted using an organic solvent and re-extracted into a 0.1% aqueous sulphuric
acid solution. The concentration of galanthamine was determined by spectrofluorometry
using excitation and emission wavelengths of 286 and 315 nm, respectively.
The fluorescence signal was linear in the range 0.05–15.0 µg/ml, and the detection
limit was 0.05 µg/ml. However, due to insufficient specificity, the data on urine,
bile and other pigmented fluids were unreliable.
Several spectrophotometric and fluorimetric procedures have also been
described to determine lycorine in Amaryllidaceae species. In these, lycorine was
first separated by chromatographic methods and was quantitatively measured
spectrophotometrically at 292 nm (Volodina et al., 1972, 1973; El-Din et al., 1983;
Makhkmova and Safonova, 1994) or fluorimetrically at excitation and emission
wavelengths of 292 and 330 nm, respectively (El-Din et al., 1983).
Electrophoretic methods
Gheorghiu et al. (1962) analysed the alkaloid extracts of Leucojum vernum and
L. aestivum by a two-dimensional electrophoresis method. The analysis was carried
out in alkaline medium and two compounds were detected and separated.
Mikhno and Levitskaya (1971) described a paper electrophoresis method for the
detection and quantification of galanthamine and securinine in biological material.
The alkaloids were separated by paper electrophoresis at pH 2 and were detected
with Dragendroff visualising agent. Galanthamine and securinine were eluted
from the paper with 0.1N HCl and were quantitatively determined by spectrophotometry
at 289 and 256 nm, respectively.
Davey et al. (1998) reported a micellar electrokinetic capillary chromatographic
method to analyse ascorbic acid and lycorine simultaneously in tissue extracts of
Crinum asiaticum. Ascorbic acid and lycorine were extracted from the plant material
using 3% metaphosphoric acid. Analysis utilised a 41 cm total length (34 cm to
detector) × 50 µm fused silica capillary with a borate buffer (pH 9.0) and 50 mM
sodium dodecyl sulphate as background electrolyte (applied voltage of +20 kV).
Compounds were detected at 185 nm by fixed-wavelength detector or at 202 and
267 nm by dual-wavelength detector. A linear detector response was observed for
lycorine between 17 and 700 µM. The detection limits at 185 and 202 nm were
17 and 1 µM, respectively.